At 2.50 p.m. last Saturday there were small, anxious clusters of us all over the streets of south Belfast. Football supporters united in a frantic search for a football match. Kick off in the Scottish Cup Final between Celtic and Rangers was only minutes away but pub after pub and club after club were refusing to show the game. Four weeks before, the crowd violence and sendings-off that scarred the climactic league game of the season between the two sides had spilled out into Belfast's bars and streets. Determined to avoid a repeat of that sectarian violence, the city's pub owners adopted a safety first policy and imposed their own de facto football black-out.

By now time was ticking by and a degree of desperation had set in. Every now and again someone would have a bright idea and run off on a scouting mission to another possible venue blessed with the dubious gifts of Sky TV. But a few minutes later they would return downcast. Just after 3.00 p.m. we played our last card and piled into a car to drive across town. The commentary on BBC Radio 5 confirmed we'd missed the start but we now exuded an air of quiet confidence. As we circled our last-chance saloon looking for a parking space someone spotted four bouncers on the door. This was a good sign. They looked ready for trouble which meant they must be showing the game. Once inside, we were told that the public bar was closed and we were instead shepherded upstairs to a cavernous, dimly-lit disco.

It was a surreal sight. There were five or six television screens of varying sizes dotted around the huge room. The wooden space that usually passed for the dance-floor was packed with people watching the match and watching them were pockets of three or four of the ubiquitous bouncers ready to move in at the slightest hint of trouble. The trademark disco darkness didn't help. During the quieter moments of a first half when the football barely edged above the mediocre it was all but impossible to gauge the composition of the watching hordes. Every now and then a sectarian rant of one hue or another could be heard but the delivery was unsure and tentative and it faded away almost as soon as it began. Best not to stick your head too far above the parapet when you are not certain what exactly you are going to find there. Being Northerners and this being the North in all its bizarre absurdity we soon got our bearings and another Saturday afternoon in Belfast settled down into an uneasy calm. But then it has always been thus. Rangers's league-clinching victory at Celtic Park a few weeks before and the violence that surrounded it were not unusual in themselves. Nor was the way in which events in Glasgow were faithfully aped on the streets here. Every three or four years the lid comes off the Old Firm pressure cooker and after that brief release the respective supporters return to a nervous status quo of mutual fear and loathing.

These flare-ups also have a happy media spin-off, allowing as they do a succession of self-righteous commentators to cogitate about the "blight of sectarianism in football". This time there was even a locally-produced BBC television documentary mapping out the events of the day. With mind-numbing predictability, its makers got exactly what they would have expected when they pointed cameras in the faces of supporters high on emotion and even higher on alcohol.

The Rangers people justified their club's strident Protestantism on the basis that it was only a reaction to their rival's Catholic roots. The Celtic fans, for their part, then paraded a series of conspiracy theories so complex and so intricate they made the shooting of John F Kennedy look like a simple, open-and-shut cases. The referees, the administrators and every journalist in the world, it would seem, are out to get them and nobody, but nobody, does anything to help.

There was also something deliciously ironic about an Irish film crew travelling to Glasgow to ask people there about the reasons for the animosity and the hatred that characterises meetings of the city's Old Firm. Anyone who has visited Glasgow in the last decade will have experienced one of Britain's most cultured cities - it knew what it was to be European and cosmopolitan when they were still bombing Belfast's city centre and Temple Bar was little more than a twinkle in the eyes of the developers. The harsh truth is that Glasgow would have left the outmoded sectarianism of Celtic and Rangers behind long ago had it not been for the hordes who travel from Ireland on alternate weeks to Celtic Park and Ibrox. If the Old Firm derby is a relic of a football age that should have been consigned to history long ago, it is largely because that is the way the Irish supporters of both clubs want it to stay. But if they are to be part of the European football explosion in the next 20 years both Celtic and Rangers have to find some way of redefining that sense of Irishness or Northern Irishness without alienating all those who stump up hard cash for season tickets year after year.

Of the two clubs, Celtic probably recognise that more acutely. The ending of the Rangers ban on signing Catholic players has dragged the club kicking and screaming into the 20th century and has fixed the spotlight on their neighbours. Celtic's Irish origins have, in large part, made the club what it is. But Fergus McCann, its erstwhile managing director, realised that there are both positive and negative elements tied up in that. A crackdown on the singing of offensive songs within Celtic Park and an anti-bigotry campaign were specifically aimed at eliminating that negativity. But the club has had to teeter along an uneasy tightrope because even the most minor reforms have been seized upon by supporters' groups here as an attempt to jettison Celtic's Irish image altogether. Given the sensitivities involved, it is a tortuous process that will require the Wisdom of Solomon over the coming decade or so.

But back in Ireland on last Saturday afternoon such lofty notions of reform and progress seemed aeons away. In Dublin they were trading sectarian chants at a "peace" international in a one-third full Lansdowne Road. And one hundred miles up the road in Belfast we were being marshalled out onto the street, the bouncers looking at us with total disdain. It was impossible not to feel cheapened by the whole, sorry experience.